The prior art histological tissue freezing process utilizes a container enclosing a cavity having a selective pressurized fluid such as dichlorodifluoromethane.
One problem with the prior art tissue freezing process is that it causes release of gases which are detrimental to the atmosphere and therefore the environment.
A related application is U.S. application Ser. No. 472,318, filed Jan. 30, 1990, entitled "Tissue Freezing Process" which issued on Aug. 27, 1991 as U.S. Pat. No. 5,042,261.